Re: [RFC PATCH] Use feature bit names in clearcpuid=
From: Thomas Gleixner
Date: Tue Sep 22 2020 - 04:03:09 EST
On Sun, Sep 20 2020 at 17:42, Borislav Petkov wrote:
> so tglx hates this clearcpuid= interface where you have to give the
> X86_FEATURE array indices in order to disable a feature bit for testing.
> Below is a first attempt (lightly tested in a VM only) to accept the bit
> names from /proc/cpuinfo too.
> I say "too" because not all feature bits have names and we would still
> have to support the numbers. Yeah, yuck.
> An exemplary cmdline would then be something like:
> clearcpuid=de,440,smca,succory,bmi1,3dnow ("succory" is wrong on
> and it says:
> [ 0.000000] Clearing CPUID bits: de 13:24 smca bmi1 3dnow
> Also, I'm thinking we should taint the kernel when this option is used.
Yes, instead of making it differently horrible, can we finally remove that
nonsense which should have never been there in the first place?